Relationship between fluvoxamine and stress barometer for nocturnal enuresis

Background: It has been reported recently that fluvoxamine (a selective serotonin reuptake inhibitor) is effective and safe for children with monosymptomatic nocturnal enuresis (MNE). However, the exact mechanism by which fluvoxamine is beneficial in the treatment of MNE remains unknown. One possibility is that it controls emotional stress. Methods: We divided children with MNE into primary MNE (n = 40) and secondary MNE (n = 7). We measured urinary 17-hydroxycorticosteroids (17-OHCS) and 17-ketosteroid sulfates (17-KS-S) as a stress barometer in children with MNE to evaluate adaptation to emotional stress before and during fluvoxamine treatment. We initially administered fluvoxamine at a dose of 25 mg at bedtime. If patients remained incontinent after 3 weeks, we increased the dose to 50 mg. Results: Fluvoxamine was effective in 26 of 28 children (93%) with primary MNE and an abnormality of the stress barometer and in six of six children (100%) with secondary MNE and an abnormality of the stress barometer. Fluvoxamine was effective in only six of 12 children (50%) with primary MNE and normality of the stress barometer and was not effective in one child with secondary MNE and normality of the stress barometer. Conclusions: The stress barometer is useful clinically for evaluating the therapeutic effect of fluvoxamine for children with MNE.